Invisible air-chamber and sponson for canoes.



PATENTED MAR. 31, 190s.

C B.'THATGHER. INVISIBLE AIR CHAMBER AND SPONSUN FR OANOBS APPLICATION FILED MAY 16. 1906.

314 vauro@ man' )f d( awww/w3 UNITED STATES PATENT OFFICE.

CALEB B. THATCIIER, OF BANGOR, MAINE. INVISIBLE AIR-CHAMBER AND SPONSON FOR CANOES.

Specification of Letters Patent.

No. 883,588. Patented March 31, 1908. Application filed May 16, 1906. Serial No. 317,120. To all whom 'it mag/concern: ribs' are then covered with ordinary canoe Be it known that I, CALEB B. THATCHER, planking C, which is made water tight in any a citizen of the United' States, residing at i suitable manner. A-canvas covering C is Bangor, in the county of Penobscot and then placed over the hull of the canoe and State of. Maine, v have invented a new and planking of the sponson and drawn over the useful Improvement in an Invisible Air- 's aces formed by the ribs between the two Chamber and Sponson for Canoes, of which l ankings and secured under the gunwales the following is a specification. l2), of the canoe, forming an invisible air tight This invention relates to air chambers and l compartment or sponson. A gunwale E, is sponson for canvas boats and more particuthen laced over the canvas and is secured to larly to invisible air chambers andsponsons the p anking C, and ribs B, so that they will for canoes, the object being to provide a be protected. sponson which extends from the gunwales From the foregoing description it will be to the water-line so that the sponson will be readily seen that the hull of the canoe can brought into contact with ,the water, as soon be made narrower so that when the sponsor) as the canoe is tilted off an even keel. is attached, a canoe of the ordinary shape This invention consists -of the novel feawill be formed. vIt will also be readily seen .tures of construction, hereinafter fully dethat by constructing a canoe as described, an'

scribed and pointed out in the claims. invisible sponson is obtained which has great In the drawings forming a part of this advantages over the sponsons now in use. specification z-i-Figure l. is a perspective View Having thus fully described my invention, ol a canoe provided with my improved sponwhat I claim as new and desire to secure by son showing the canvas broken away. Fig. Letters Patent is 2 is a section taken o'n lines 2-2 of Fig. 1. A canoe having tapering 'curved ribs cut to Fig. 3 is a section taken on lines 3 3 of Fig. conform to the curvature of the hull secured 1. Fig. 4 is a section taken on lines 4 4 of to the outside of the planking and extending Fig. 2. I from the gunwales to the water line, said In constructing a `canoe with my improved ribs gradually decreasing in width and length sponson I employ a hull A, of the ordinary `from the center towards each end, planklng construction before the canvas has been put secured on said ribs, end canvas secured over on, which is air and water tight, then I sesaid hull and ribs having its side edges secure to the outside of the hull spaced curved tapering ribs B, which extend from the gunwales of the canoe tothe water line. These ribs are widest at the center ofthe canoe, and l gradually decrease in vWidth and length towards each end to where they stop. 'Ihe i ing an invisible air tight compartment.

CALEB B. THATCHER. 'Witnessesz H. J. CHAPMAN, GEO. S. CLARK.

cured under the gunwales of the canoe form- 

